Occluder insertion system

ABSTRACT

System for inserting a self-expandable occluder into a patient and for releasing the occluder in the left atrial appendage of the patient, the system including an insertion unit which has a drive unit and an insertion catheter having an outer tube and an inner tube extending through the outer tube, wherein a proximal end region of the occluder is movement-coupled to the outer tube, and wherein a distal end region of the occluder is movement-coupled to the inner tube.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. application Ser. No.17/422,000, filed Jul. 9, 2021, which is the U.S. National StageApplication of PCT Application No. PCT/EP2020/050432, filed Jan. 9,2020, which claims priority to German application no. 10 2019 100 531.0,filed Jan. 10, 2019, the entirety of each of which is herebyincorporated by reference.

BACKGROUND

The invention relates to a system for inserting a self-expandableoccluder into a patient and for releasing the occluder in the leftatrial appendage (auricula cordis sinistra) of the patient. Theinvention also relates to an associated insertion unit.

The auriculae atrii or atrial appendages are protuberances of the atriaof the heart in mammals. The left atrial appendage (LAA), knownmedically as the auricula cordis sinistra, is located next to thepulmonary artery tract and is a frequent site for blood clots that canlead to a stroke, especially in patients with atrial fibrillation.Preventing thrombi in the left atrial appendage is therefore aneffective stroke prophylaxis in vulnerable patients.

For this stroke prophylaxis, implants have been developed that areintroduced into the protuberances and close the access, for exampleusing a Teflon film. These implants are referred to as LAA (left atrialappendage) occluders. These implants are inserted into the protuberancesand anchored there in particular by means of anchoring elements, sothat, in particular via the proximal end region thereof, they close offthe access into the protuberances in a fluid-tight manner. Insertionmostly takes place using endovascular techniques, i.e. in particular bymeans of an insertion catheter through which the implant is brought tothe place of use. The occluders are brought to the place of use inparticular in a reduced-volume form, and expanded there. Self-expandingmaterials are generally used for the occluders, for example shape-memoryalloys. An occluder of this kind is previously known from WO 2015/079023A1.

It is known to use a guide wire to insert an occluder into the leftatrial appendage of a patient. The guide wire, as disclosed for examplein WO 2015/079023 A1, is screwed tightly to an internal thread of theoccluder by means of an external thread. The occluder is then brought toits intended position in the region of the left atrial appendage. Oncethe occluder has assumed its self-expanded shape at its intendedlocation, the guide wire can be detached from the occluder by unscrewingthe guide wire from the occluder. An occluder of this kind is alsodisclosed in WO 2006/036837 A2, wherein the occluder is formed in twoparts and is provided for closing an atrial septal defect. In thisprocess, undesirable torques can act on the occluder in particular and,in the worst case, even lead to the occluder becoming detached from itsintended position. There is therefore a need to rectify thesedisadvantages.

There is also a need to be able to move an occluder as easily aspossible into an insertion position, which can in particular be acompressed position, in order to bring the occluder to the left atrialappendage in this insertion position.

It is also known from DE 10 2009 020 012 A1 and U.S. Pat. No. 5,201,757that a stent can be brought into its self-expanded shape by moving twoelements of a catheter in opposite directions.

EP 2 266 465 A1 l discloses an occlusion instrument wherein no partsprotrude beyond the proximal end of the occlusion instrument duringinsertion.

A handling unit for inserting a prosthesis is known from US 2017/0056222A1, wherein two elements of the handling unit can be rotated relative toone another such that an outer tube and an inner tube move intranslation relative to one another and the shape expands from the gapthat forms.

WO 2006/036837 A2 discloses an insertion system for a two-part occludercomprising an outer tube and an inner guided wire, wherein the outertube cooperates at its distal end with the proximal end of the occluderby means of an internal thread and the inner guided wire cooperates atits distal end with the distal end of the occluder.

WO 2017/157316 A1 shows an insertion system for a foldable occluder withan outer tube and an inner tube, wherein the outer tube cooperates withthe proximal end of the occluder by means of an inner thread and theinner tube cooperates with the distal end of the occluder by means of anouter thread.

Overall, the problem addressed by the present invention is thereforethat of developing the known prior art.

SUMMARY OF THE INVENTION

This problem is solved by a system for inserting a self-expandableoccluder into a patient and for releasing the occluder in the leftatrial appendage of the patient. The system comprises an insertion unitwhich has a drive unit and has an insertion catheter comprising an outertube and an inner tube extending through the outer tube. A proximal endregion of the occluder is movement-coupled to the outer tube, while adistal end region of the occluder is movement-coupled to the inner tube,wherein a distal end of said outer tube is disposed inside said occludeduring insertion of the occluder. The drive unit interacts with theinner tube and the outer tube of the occluder in such a way that, whenactuated, the inner tube can be moved in a distal or proximal directionand the outer tube can be moved in the proximal or distal direction, sothat the proximal end and the distal end of the occluder can be movedaway from or toward one another.

Movement-coupling the proximal end region of the occluder to the outertube and the distal end region of the occluder to the inner tube meansthat the proximal end and the distal end of the occluder can be movedaway from or toward one another. In order to insert the occluder into apatient and guide the occluder to the left atrial appendage, the innertube can therefore first be moved in the distal direction, while theouter tube is moved in the proximal direction. In so doing, the proximalend and the distal end of the occluder can be moved away from oneanother in order to bring the occluder into an insertion position. Inthis insertion position, the occluder is accordingly arranged in acompressed form, so that it has an increased length but a reduceddiameter. As a result, it can be brought to the left atrial appendagethrough blood vessels in particular.

By contrast, in order to release the occluder in the left atrialappendage, the inner tube can be moved in the proximal direction, whilethe outer tube can be moved in the distal direction. In so doing, theproximal end and the distal end of the occluder move toward one another,with the occluder developing in particular into its self-expanded shape.In so doing, the length of the occluder is reduced while its diameterincreases. During this release process, the occluder comes to restagainst the left atrial appendage, in order to thus close the leftatrial appendage by means of the occluder.

Overall, the position of the occluder can be changed in a particularlysimple manner, in order to transfer the occluder into an insertionposition in which the occluder can be brought to the left atrialappendage of a patient in a particularly simple manner, and in order tobe able to release the occluder, the occluder developing in particularinto its self-expanded shape and, after release, tightly closing theleft atrial appendage.

In an advantageous development of the invention, the outer tube ends infront of the inner tube in the distal direction. As a result, theproximal end region of the occluder can be movement-coupled to the outertube and the distal end region of the occluder can be movement-coupledto the inner tube in a particularly simple manner.

In a further advantageous embodiment of the invention, the occludercomprises a frame that has a tubular proximal end region through whichthe insertion catheter is inserted into the occluder. In this way, theinsertion catheter can be inserted into the occluder in a particularlysimple manner. The distal end of the outer tube can in this case belocated directly after the tubular proximal end region in the distaldirection, so that the outer tube interacts in particular with thetubular proximal end region of the occluder for the purpose of movementcoupling. It is conceivable for the outer tube to interact with thetubular proximal end portion in a form-fitting or force-fitting manner.Furthermore, the occluder develops in particular into its self-expandedshape so that, from the insertion position, when the outer tube moves inthe distal direction, the occluder can support the movement byintrinsically developing into the expanded position.

It is also advantageous for the occluder to comprise a pot-shaped distalend region on which the inner tube of the insertion catheter isarranged. The distal end region of the inner tube can consequently beinserted in particular into the pot-shaped distal end region of theoccluder and end therein. The pot-shaped distal end region thereforecomprises in particular a circular-cylindrical sheath portion and a baseportion. Consequently, movement coupling between the inner tube and thedistal end region of the occluder can be provided in particular in thedistal direction. It is conceivable for the inner tube to be arranged inthe distal pot-shaped end region in a form-fitting or force-fittingmanner. As a result, movement coupling between the inner tube and thedistal pot-shaped end region of the occluder can also be provided whenthe inner tube is moved in the proximal direction. Furthermore, theoccluder develops in particular into its self-expanded shape so that,from the insertion position, when the inner tube moves in the proximaldirection, the occluder can support the movement by intrinsicallydeveloping into the expanded position.

It is particularly preferred if, in order to be inserted into a patient,the occluder can be moved into an insertion position by a distal end ofthe inner tube and a distal end of the outer tube being moved relativeto one another and away from one another, so that the proximal end andthe distal end of the occluder can be moved away from one another. Inthis insertion position, the occluder can in particular have a reduceddiameter and can thus be compressed. In this case the occluder can havean increased length, and therefore, in the insertion position, theoccluder has a reduced diameter but a greater length by comparison withthe release position. In this insertion position, the occluder can bebrought up to the left atrial appendage particularly easily.

It is particularly preferred if, in order to release the occluder, thedistal ends of the inner tube and the outer tube can be moved toward oneanother in such a way that the proximal end and the distal end of theoccluder can be moved toward one another. In particular, it isconceivable that, during the release process, the occluder develops inparticular into its self-expanded shape so that, from the insertionposition, when the inner tube moves in the proximal direction or theouter tube moves in the distal direction, the occluder intrinsicallydevelops into the expanded position.

In this case, a central part of the occluder between the proximal endand the distal end can keep its position substantially unchanged duringthe release of the occluder. In order to release the occluder at itsintended position in the region of the left atrial appendage, the distalends of the inner tube and the outer tube are consequently moved towardone another, so that the proximal end and the distal end of the occluderalso move toward one another. Because the occluder can in particular beself-expanding, the occluder can in particular develop into itsself-expanded position during the release process. In the end position,the occluder can come to rest against the inside of the left atrialappendage and tightly close the left atrial appendage, in order toreduce the risk of thrombus formation and the risk of stroke associatedtherewith. In the end position, the occluder can adopt itsself-expanding final shape. However, it is also conceivable that the endposition of the occluder, in which it rests tightly against the leftatrial appendage, is already reached before the self-expanded finalshape is reached, and then the occluder cannot deform any further.

It is conceivable that the occluder has a central axis which extendsthrough the proximal end region and the distal end region. The occludercan extend around this axis. In the insertion position, the occluder canhave a center point along this axis between the proximal end and thedistal end. When the occluder is then released, in particular theproximal end and the distal end of the occluder can be moved toward oneanother in such a way that the center point of the occluder maintains orsubstantially maintains its position. This makes it possible to arrangeand release the occluder on the left atrial appendage in a particularlyprecisely positioned manner. In its end position, the occluder can inparticular have a spherical outer contour, so that the center point canalso be the center point of the circular outer contour.

It is also particularly preferred if the drive unit has a firsttransmission element that has a first transmission thread, a secondtransmission element that has a second transmission thread, and anactuating element that can be actuated by an operator and has a firstdrive thread and a second drive thread. The first transmission elementis in this case movement-coupled to the inner tube. The secondtransmission element is movement-coupled to the outer tube. The firstdrive thread interacts with the first transmission thread, while thesecond drive thread interacts with the second transmission thread, inorder to move the distal ends of the outer tube and the inner tubetoward or away from one another. Movement coupling between the driveunit and the outer tube or inner tube of the insertion catheter canthereby be provided in a particularly simple manner. The first and thesecond drive thread can be formed as one piece. In particular, theactuating element can be formed as one piece overall. When the actuatingelement is actuated, the distal ends of the outer tube and the innertube can consequently be moved toward or away from one another at thesame time. The first transmission thread and the second transmissionthread can be synchronous and the first drive thread and the seconddrive thread can be synchronous, such that when the actuating element isactuated, the inner tube and the outer tube are each moved in oppositedirections by the same distance.

The first drive thread is advantageously designed as a first internalthread which interacts with the first transmission thread which isdesigned as an external thread. Furthermore, the second drive thread isadvantageously designed as a second internal thread which interacts withthe second transmission thread which is designed as an external thread.The first and the second drive thread can be formed as one piece withone another. Overall, a movement coupling and a synchronous movement inopposite directions can be achieved thereby in a particularly simplemanner.

The outer tube preferably has, at its distal end region, at least onelatching finger-like portion, in particular two or more, which interactswith the proximal end region of the occluder for the purpose of movementcoupling. A particularly simple movement coupling can be achieved inthis manner. In this case, the latching finger-like portion can interactin particular with the tubular proximal end portion of the occluder andengage behind it in particular for the purpose of movement couplingduring a movement in the proximal direction. The outer tube can inparticular be formed as one piece.

In a particularly preferred development of the invention, the firsttransmission element interacts with a Luer connector arranged on theinner tube for the purpose of movement coupling to the inner tube. ALuer connector can therefore be arranged on the inner tube. Thisconnector can be arranged, for example, on the first transmissionelement for the purpose of movement coupling.

In a particularly preferred development of the invention, the latchingfinger-like portion is arranged on the proximal end region of theoccluder in a form-fitting manner when the inner tube is arranged in theoccluder. In particular, the latching finger-like portion can beelastically yielding and, starting from a rest position, can bedeflected out of this rest position after the inner tube is insertedthrough the outer tube. When the inner tube is then passed through theouter tube, the latching finger-like portion cannot deflect radiallyinward and thus a stable form-fit between the proximal end region of theoccluder and the latching finger-like portion can be established.

It is particularly preferred if, in order to remove the insertioncatheter from the occluder, the inner tube can first be pulled out ofthe occluder. As soon as the inner tube is pulled out of the occluderthrough the outer tube, the outer tube can then be pulled out of theoccluder.

The form-fitting connection between the outer tube and the proximal endregion of the occluder can therefore only be broken when the inner tubehas been pulled out of the occluder through the outer tube. As statedabove, in order to release the occluder, the distal end and the proximalend of the occluder can consequently be moved toward one another bymeans of the outer tube and the inner tube, by the distal ends of theouter tube and the inner tube being moved toward one another. In sodoing, the occluder pushes into its self-expanded shape.

As soon as this process of moving the proximal and distal ends of theoccluder toward one another is completed, the insertion catheter can bepulled off the occluder in a particularly simple manner by first pullingthe inner tube out of the occluder through the outer tube. The outertube can then be pulled out of the occluder, wherein in particular thelatching finger-like portion at the distal end region of the outer tubecan be moved elastically inward in the radial direction in order to pullthe outer tube out of the in particular tubular proximal end portion ofthe occluder.

As a result of this process, undesired torque transmission from theinsertion catheter to the occluder can therefore be substantiallycompletely or in particular completely prevented. This can minimize oreliminate the risk of the occluder being released from its intendedposition on the left atrial appendage when the insertion catheter isremoved from the occluder. After the insertion catheter has beenremoved, the occluder can push completely into its self-expanded shapeand, in particular, close the left atrial appendage in a completelyfluid-tight manner.

The insertion unit advantageously has a housing which can be held by anoperator, wherein the transmission elements and the actuating elementare arranged in or on the housing. An operator, for example a surgeon,can accordingly hold the housing in their hand, and therefore thehousing can be designed in the manner of a handle. The transmissionelements and/or the actuating element can be arranged in or on thehousing.

The actuating element is preferably rotatably arranged on the housing.The housing can have a central longitudinal axis and the actuatingelement can be rotated about the central longitudinal axis. Theactuating element can in particular be formed as one piece, and inparticular be hollow-cylindrical and have an internal thread.

The problem stated at the outset is also solved by an insertion unit fora system according to the invention. Accordingly, the insertion unitcomprises a drive unit and an insertion catheter comprising an outertube and an inner tube extending through the outer tube. By means of theinsertion catheter, an occluder can be moved into an insertion positionin a particularly simple manner, in order to be supplied to the leftatrial appendage. The occluder can then be transferred into its endposition by means of the insertion unit in order to close the leftatrial appendage. Finally, the insertion catheter can be pulled off theoccluder in a particularly simple manner, in particular without asubstantial torque being transmitted to the occluder. As a result, theoccluder can be positioned on the left atrial appendage in a morereliable and more secure manner.

BRIEF DESCRIPTION OF THE DRAWINGS

Further details and advantageous embodiments of the invention can befound in the following description, on the basis of which the embodimentof the invention shown in the figures is described and explained in moredetail. In the drawings:

FIG. 1 is a schematic plan view of an occluder according to anembodiment that is arranged on the left atrial appendage;

FIG. 2 is a schematic perspective view of the occluder according to FIG.1 ;

FIG. 3 is a plan view of one half of the occluder according to FIG. 2 ;

FIG. 4 is a cutaway schematic view of a frame portion of the occluderaccording to FIG. 2 ;

FIG. 5 is a perspective schematic view of an insertion unit according toan embodiment;

FIG. 6 is a schematic cross-sectional view of the insertion unitaccording to FIG. 1 , with an occluder arranged thereon in the insertionposition;

FIG. 7 is a schematic cross section of the insertion unit according toFIG. 1 with the occluder arranged thereon, in a configuration before theinsertion unit is removed from the occluder;

FIG. 8 is a schematic cross section of a region around the proximal endof the occluder, with the insertion unit arranged thereon;

FIG. 9 is a view based on FIG. 8 , with the inner tube of the insertionunit removed from the occluder; and

FIG. 10 is a view of a proximal region of the insertion unit with a Luerconnector detached from the insertion unit.

DETAILED DESCRIPTION

Firstly, FIG. 1 schematically shows the left atrial appendage of apatient, denoted with reference sign 10. To reduce the risk of a stroke,an occluder 12 is introduced into the left atrial appendage 10 in orderto close the access to the left atrial appendage 10.

The occluder 12 initially comprises a frame 14 formed as one piece. Thisframe comprises a proximal tubular portion 16 and a pot-shaped distalend portion 18. The pot-shaped distal end portion 18 comprises acircular-cylindrical sheath portion 20 and a base portion 22, in orderto form a pot-shaped structure. The occluder has a net-like frameportion 24 between the two end portions 16, 18. This net-like frameportion 24 can be seen particularly clearly in a cut-open form in FIG. 4. Starting from the proximal tubular end portion 16, the net-like frameportion 24 initially has a number of webs 26. These merge into abranching network of webs 25 in order to form the net structure. In sodoing, diamond-shaped structures 28 are formed. In the distal direction29, the webs 25 converge again into individual webs 30 which open intothe distal end portion 18.

In the arranged state (cf. FIG. 1 ), the occluder 12 has a proximalhemisphere 32 and a distal hemisphere 35. A number of first anchoringmeans 34 are provided in the region of the proximal hemisphere 32. Theseextend along a circular line along the circumference and are in the formof hooks having end portions pointing in the proximal direction 27.Second anchoring means 36 are formed in the region of the distalhemisphere 35. These likewise extend along a circular line along thecircumference, have a rod-like shape and protrude obliquely from thecircumferential surface in the proximal direction 27. The anchoringmeans 34, 36 are also formed as one piece with the frame 14.

The frame 14 of the occluder 12 consists of a self-expanding material,for example a shape-memory alloy, in particular a nitinol alloy. Theexpanded shape impressed on the occluder 12 is spherical (cf. FIG. 2 ).The occluder 12 has a longitudinal axis 38 extending in the proximal ordistal direction through its center point. This longitudinal axis 38also extends through the central longitudinal axis of the tubularproximal end portion 16 and through the central longitudinal axis of thedistal end portion 18 (cf. FIG. 2 ). The proximal hemisphere 32 iscompletely covered by a biological tissue 40. This biological tissue 40is in particular a biological membrane. In particular, it can be thepericardium membrane. The tissue 40 comprises openings, such that thefirst anchoring means 34 protrude through the openings. The tissue 40also has an insertion opening in order to insert an insertion catheterthrough the proximal tube portion 16 into the occluder 12. When theinsertion catheter has been removed from the occluder 12 after theoccluder 12 has been released, the elastically yielding tissue 40 cancontract in such a way that the insertion opening is closed in asubstantially fluid-tight manner, so that overall the tissue 40 closesoff the proximal hemisphere 32 in a substantially fluid-tight manner andsubstantially covers the frame 14. As indicated schematically bysurgical threads 42, the tissue is sewn to the frame 14 by means of PTFEthreads.

In the vicinity of the parting plane 44 of the proximal hemisphere 32and the distal hemisphere 35, a number of X-ray markers 38 are placedover the circumference in the region of the proximal hemisphere 32.These allow the occluder 12 to be precisely positioned in the leftatrial appendage. A surgeon can consequently place the occluder 12 in aparticularly precisely positioned manner.

Overall, by providing the biological tissue 40, an occluder 12 that hascomparatively high biocompatibility can be provided. In this case, afterthe occluder 12 has been arranged on the left atrial appendage, thepatient's natural tissue can grow over the biological tissue 40. As aresult of the biological tissue 40 used, there is overall highbiocompatibility and thus an increased probability that surgicalintervention to close the left atrial appendage is successful.

In the following, a system for inserting the occluder 12 into a patientand for releasing the occluder 12 in the left atrial appendage 10 of thepatient is described according to one embodiment:

FIG. 5 shows an insertion unit 100 as a whole. This comprises both adrive unit 102 and an insertion catheter 104. The insertion catheter 104comprises an inner tube 108 and an outer tube 110. The inner tube 108extends through the outer tube 110. Moreover, the outer tube 110 ends infront of the inner tube 108 in the distal direction 29. The drive unit102 comprises a housing 114 which can be held in the hand of anoperator, in particular a surgeon, and which overall has an elongateshape.

The drive unit 102 also comprises an actuating element 116 which isrotatably arranged in the housing 114. The actuating element 116 ishollow and has a first drive thread 118 and a second drive thread 120,the first drive thread 118 being proximal to the second drive thread 120(cf. FIGS. 6 and 7 ). The actuating element 116 is in particular formedas one piece.

A first transmission element 122 and a second transmission element 124are also arranged in the housing 114. The two transmission elements 122,124 overall have a helical shape. The first transmission element 122 hasa thread portion 126 and a head portion 128. The second transmissionelement 124 correspondingly has a thread portion 130 and a head portion132. The two transmission elements 122, 124 can in particular each beformed as one piece. The first transmission element 122 is in this casemovement-coupled to the inner tube 108, while the second transmissionelement 124 is movement-coupled to the outer tube 110. The head portion128 of the first transmission element 122 interacts with a Luerconnector 134 that is fastened to the inner tube 108. The Luer connector134 is detachably arranged on the head portion 128 of the firsttransmission element 122.

The head portion 132 of the second transmission element 124 interactswith the outer tube 110 for the purpose of movement coupling. The outertube 110 is detachably arranged on the head portion 132.

At the distal end of the outer tube 110, said tube has two latchingfinger-like end portions 136, which can be seen particularly clearly inFIG. 9 . These are formed as one piece with the outer tube 110 and canbe deformed in an elastically yielding manner. Overall, the mode ofoperation of the insertion unit 100 is then as follows:

In order to insert the occluder 12 into the left atrial appendage 10,the insertion catheter 104 is firstly arranged on the occluder 12 inorder to form a system consisting of the insertion unit 100 and occluder12, in order to bring the occluder 12 to the left atrial appendage 10and then release the occluder 12.

The occluder 12 is initially in its self-expanded shape and thus has aspherical outer contour (cf. FIG. 2 ). The outer tube 110 is insertedinto the occluder 12 through an insertion opening (not shown) in thebiological tissue 40 of the occluder 12 and through the tubular proximaltube portion 16. The inner tube 108 is then passed through the occluder12 and the outer tube 110 and arranged on the distal pot-shaped endportion 18 of the occluder 12. The latching finger-like portions 136 aresecured against elastic deformation in the radially inward direction bythe inner tube 108, so that the latching fingers 136 come to restagainst the proximal tubular portion 16 in a form-fitting manner.

The housing 114 can then be picked up by an operator, in particular asurgeon, and the actuating element 116 can be rotated. As shown in FIG.6 , the actuating element 116 is first rotated in such a way that thehead-like portions 128, 132 of the two transmission elements 122, 124are moved toward one another. As a result, the distal end 137 of theouter tube 110 and the distal end 138 of the inner tube 108 are movedaway from one another. As a result, the distal end 140 of the occluder12 is displaced in the distal direction 29, while the proximal end 142of the occluder is displaced in the proximal direction 27. Overall, theoccluder 12 is in this case transferred into an insertion position, sothat the occluder 12 as a whole assumes a compressed form in which ithas, by comparison with the self-expanded form, an elongate outercontour having a reduced diameter d (cf. FIG. 6 ). In this compressedinsertion position, the occluder 12 can be inserted into a blood vesseltogether with the insertion catheter 104 and then brought further up tothe left atrial appendage to the intended position. The position of theoccluder 12 can be determined by means of the X-ray markers 38. Thecentral region of the occluder 12, i.e. the region of the X-ray markers38, is intended to come to rest against the left atrial appendage.

In order to then release the occluder 12, the actuating element 116 isrotated, as shown in FIG. 7 , such that the head-like portions 128, 132are moved away from one another. As a result, the inner tube 108 ismoved in the proximal direction 27, while the outer tube 110 is moved inthe distal direction 29. In the course of this relative movement, theproximal end 142 of the occluder 12 and the distal end 140 of theoccluder 12 are moved toward one another. As a result, the diameter d ofthe occluder 12 increases. The occluder 12 pushes into its self-expandedshape, so that the proximal end 142 and the distal end 140 of theoccluder push toward one another.

In this case, the position of the central part of the occluder 12remains in particular unchanged, which is shown in FIGS. 6 and 7 withreference to the center line 144. The center line 144 extends throughthe middle of the occluder 12 between the proximal end 142 and thedistal end 140 when said occluder, as shown in FIG. 6 , has reached theintended position. The middle of the occluder 12 therefore remains inthe correct position and thus does not change position when the occluderis released, as shown in FIG. 7 .

In the position shown in FIG. 6 , the inner tube 108 is held on thepot-shaped distal end portion 18 of the occluder 12 in a force-fittingmanner in the proximal direction 27. Consequently, during a proximalmovement of the inner tube 108, the distal end portion 18 of theoccluder 12 is also moved in the proximal direction 27. When theoccluder 12 is transferred into a position as shown in FIG. 7 , theforce of the force fit is reduced so that, as shown in FIG. 10 , theLuer connector 134 can be detached from the head-like portion 128 withcomparatively little effort, so that the Luer connector 134 and thus theinner tube 108 can be pulled off the occluder 12 through the outer tube110.

Then, as shown in FIG. 10 , the outer tube 110 can be pulled off theoccluder 12, since the latching finger-like portions 136 can now moveelastically radially inward. The occluder 12 can then assume its releaseposition in which it can assume its self-expanded shape, as shown inFIG. 1 , or in any case pushes into its self-expanded final shape andthus tightly closes the left atrial appendage. When the insertioncatheter has been removed from the occluder 12 after the occluder 12 hasbeen released, the elastically yielding tissue 40 can contract in such away that the insertion opening (not shown) in the tissue 40 is closed ina substantially fluid-tight manner, so that overall the tissue 40 closesoff the proximal hemisphere 32 in a substantially or completelyfluid-tight manner and substantially or completely covers the frame 14.The patient's skin can then grow over the biological tissue 40, so thatthe left atrial appendage can be permanently and stably closed.

As a result of the proposed configuration, the insertion catheter 104can be pulled off the occluder 12 in a particularly simple manner. Thiscan be achieved in particular without, or almost without, a torque beingexerted on the occluder 12. This reduces the risk of the occluder beingdisplaced from its intended position in an undesirable manner when theinsertion catheter 104 is pulled off the occluder 12.

1. System for inserting a self-expandable occluder into a patient andfor releasing the occluder in the left atrial appendage of the patient,the system comprising an insertion unit which has a drive unit and hasan insertion catheter comprising an outer tube and an inner tubeextending through the outer tube, wherein a proximal end region of theoccluder is movement-coupled to the outer tube, and wherein a distal endregion of the occluder is movement-coupled to the inner tube, wherein,in order to release the occluder, the drive unit interacts with theinner tube and the outer tube such that, when actuated, the inner tubecan be moved in a distal or proximal direction and the outer tube can bemoved in the proximal direction or distal direction, so that the distalend and the proximal end of the occluder can be moved away from ortoward one another, wherein, during insertion of the occluder, a distalend of the outer tube is disposed inside the occluder.
 2. The system ofclaim 1, wherein the outer tube comprises at least one latchingfinger-like end portion at its distal end region, and wherein thelatching finger-like end portion cooperates with the proximal end regionof the occluder only when the inner tube is disposed inside the outertube.
 3. The system of claim 1, wherein the latching finger-like portionis configured to deflect from a rest position after insertion of theinner tube through the outer tube and to not deflect radially inward. 4.System according to claim 1, wherein the outer tube ends in front of theinner tube in the distal direction.
 5. System according to claim 1,wherein the occluder comprises a frame having a tubular proximal endportion through which the insertion catheter is inserted into theoccluder.
 6. System according to claim 1, wherein the occluder comprisesa pot-shaped distal end region on which the inner tube of the insertioncatheter is arranged.
 7. System according to claim 1, wherein, in orderto be inserted into a patient, the occluder can be transferred into aninsertion position by moving a distal end of the inner tube and thedistal end of the outer tube relative to one another and away from oneanother, so that the proximal end and the distal end of the occluder canbe moved away from one another.
 8. System according to claim 7, wherein,in order to release the occluder, the distal ends of the inner tube andthe outer tube can be moved toward one another such that the proximalend and the distal end of the occluder can be moved toward one another,wherein a central part of the occluder between the proximal end and thedistal end keeps its position substantially unchanged during the releaseof the occluder.
 9. System according to claim 1, wherein the drive unithas a first transmission element that has a first transmission thread, asecond transmission element that has a second transmission thread, andan actuating element that can be actuated by an operator and has a firstdrive thread and a second drive thread, wherein the first transmissionelement is movement-coupled to the inner tube, and wherein the secondtransmission element is movement-coupled to the outer tube, and whereinthe first drive thread interacts with the first transmission thread andthe second drive thread interacts with the second transmission thread inorder to move the distal ends of the outer tube and the inner tubetoward or away from one another.
 10. System according claim 1, whereinthe first drive thread is designed as a first internal thread whichinteracts with the first transmission thread that is designed as anexternal thread, and wherein the second drive thread is designed as asecond internal thread which interacts with the second transmissionthread which is designed as an external thread.
 11. System according toclaim 9, wherein the first transmission element interacts with a Luerconnector arranged on the inner tube for the purpose of movementcoupling to the inner tube.
 12. System according to claim 2, wherein thelatching finger-like portion interacts with the proximal end region ofthe occluder in a form-fitting manner when the inner tube is arranged inthe occluder.
 13. System according to claim 2, wherein, in order toremove the insertion catheter from the occluder, the inner tube canfirst be pulled out of the occluder, and then the outer tube can bepulled out of the occluder as soon as the inner tube has been pulled outof the occluder through the outer tube.
 14. System according to claim 1,wherein the insertion unit has a housing which can be held by anoperator, and wherein the transmission elements and the actuatingelement are arranged in or on the housing.
 15. System according to claim9, wherein the actuating element is rotatably arranged on the housing.16. Insertion unit comprising a drive unit and an insertion cathetercomprising an outer tube and an inner tube extending through the outertube for use in a system for inserting a self-expandable occluder into apatient and for releasing the occluder in the left atrial appendage ofthe patient, wherein a proximal end region of the occluder ismovement-coupled to the outer tube, and wherein a distal end region ofthe occluder is movement-coupled to the inner tube, wherein, in order torelease the occluder, the drive unit interacts with the inner tube andthe outer tube such that, when actuated, the inner tube can be moved ina distal or proximal direction and the outer tube can be moved in theproximal direction or distal direction, so that the distal end and theproximal end of the occluder can be moved away from or toward oneanother, wherein, during insertion of the occluder, a distal end of theouter tube is disposed inside the occluder.